He did not hit off the backfoot every time. And it is not inherently wrong to hit off the backfoot anyway (Nadal do it very often for ex).

But your hip rotation could be more pronounced, you could stand closer to baseline on those balls, the follow through is not complete somtimes, esp on backhand, the accelleration looks stiff/tense, the footwork could be more fluid.

But to conclude, nothing major wrong in my mind. You just need much more practice with good sparring partners, developing the areas i mentioned. (that is for groundstrokes). then Serve, return of serve, volley, dropshot and so forth, we dont know that yet.

Nice job. The backhand could be more fluid, you tend to let the follow through be abbreviated. Make sure you have a nice flexibility program for you core as you seem a tad stiff.

Even more than how you stokes look, the question is how effective are they? Are you getting depth and spin? Are you able to hit where you aim? Are your unforced errors low? Are you competing and winning?

You're supposed to load on the back foot, but not swing leaning back, like the OP was. If you watch Federer in a match, he hits with his weight moving foreword 95% of the time. That video is him warming up casually.